<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style type="text/css">
			/* :link选择所有未访问链接 */
			a:link{
				background-color: #00FFFF;
			}
			a:visited{
				background-color: snow;
			}
		</style>
	</head>
	<body>
		<a href="http://www.nj-jp.com/nav/1.html">连接</a>
		<a href="">为访问</a>
		<a href="before.html">没访问</a>
		<a href="focus.html">www</a>
	</body>
</html>
